Image: International Society for Microbial Ecology ISME: "Microbial community composition predicts bacterial production across ocean ecosystems" Authors: Elizabeth Connors1,2,*, Avishek Dutta3,4, Rebecca Trinh5, Natalia Erazo1, Srishti Dasarathy1, Hugh Ducklow5, J.L. Weissman6,7, Yi-Chun Yeh6 , Oscar Schofield8 , Deborah Steinberg9, Jed Fuhrman6 , Jeff S. Bowman1,2 Abstract: Microbial ecological functions are an emergent property of community composition. For some ecological functions, this link is strong enough that community composition can be used to estimate the quantity of an ecological function. Here, we apply random forest regression models to compare the predictive performance of community composition and environmental data for bacterial production (BP). Using data from two independent long-term ecological research sites—Palmer LTER in Antarctica and Station SPOT in California—we found that community composition was a strong predictor of BP. The top performing model achieved an R2 of 0.84 and RMSE of 20.2 pmol L−1 hr−1 on independent validation data, outperforming a model based solely on environmental data (R2 = 0.32, RMSE = 51.4 pmol L−1 hr−1). We then operationalized our top performing model, estimating BP for 346 Antarctic samples from 2015 to 2020 for which only community composition data were available. Our predictions resolved spatial trends in BP with significance in the Antarctic (P value = 1 × 10−4) and highlighted important taxa for BP across ocean basins. Our results demonstrate a strong link between microbial community composition and microbial ecosystem function and begin to leverage long-term datasets to construct models of BP based on microbial community composition. Keywords: bacterial production; community structure; microbial ecological function; random forest regression. Author Affiliations: 1 - Scripps Institution of Oceanography, UC San Diego, La Jolla, CA 92037, United States2 - Scripps Polar Center, UC San Diego, La Jolla, CA 92037, United States3 - Department of Geology, University of Georgia, Athens, GA 30602, United States4 - Savannah River Ecology Laboratory, University of Georgia, Aiken, SC 29802, United States5 - Lamont-Doherty Earth Observatory, Columbia University, New York, NY 10964, United States6 - Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, United States7 - Department of Biology, The City College of New York, New York, NY 10003, United States8 - Coastal Ocean Observation Laboratory, Institute of Marine and Coastal Sciences, School of Environmental and Biological Sciences, Rutgers University, New Brunswick, NJ 08901-8520, United States9 - Virginia Institute of Marine Science, College of William & Mary, Gloucester Point, VA 23062, United States *Corresponding author: Elizabeth Connors, Scripps Institution of Oceanography, UC San Diego, La Jolla, CA 92037, United States. Email: econnors@ucsd.edu Type of News/Audience: Department News Tags: microbial ecological Research Areas: Geomicrobiology Read More: The ISME Journal (Volume 18, Issue 1)
